(1) You must not drop any material to any point lying outside the exterior walls of the structure unless the area is protected in accordance with WAC 296-155-775(12).

(2) All materials chutes, or sections thereof, at an angle of more than 45° from the horizontal, must be entirely enclosed, except for openings equipped with closures at or about floor level for the insertion of materials. The openings must not exceed 48 inches in height measured along the wall of the chute. At all stories below the top floor, you must keep such openings closed when not in use.

(3) You must install a gate in each chute at or near the discharge end. A competent employee must be assigned to control the operation of the gate, and the backing and loading of trucks.

(4) When operations are not in progress, you must securely close off the area surrounding the discharge end of a chute.

(5) You must protect any chute opening, into which workers dump debris, by a standard guardrail between 39 and 45 inches above the floor or other surface on which the employees stand to dump the material. You must solidly cover over any space between the chute and the edge of openings in the floors through which it passes.

(6) Where the material is dumped from mechanical equipment or wheelbarrows, you must provide a securely attached toeboard or bumper, not less than 4 inches thick and 6 inches high, at each chute opening.

(7) Chutes must be designed and constructed of such strength as to eliminate failure due to impact of materials or debris loaded therein.